Safety helmets, commonly referred to as "hard hats", provide limited protection against head and eye injury which might be caused by hazardous working conditions. Safety helmets include a hard shell and a suspension harness mounted within the shell which work together to reduce the impact of falling objects which strike the top of the shell. Safety goggles are sometimes worn with the hard hat and include an elastic strap which holds the goggles securely about the wearer's head. The purpose of the goggles is to prevent eye injury due to flying objects, and also protect the eyes from exposure to smoke, noxious fumes and corrosive fluids.
The wearing of safety goggles is required by certain industrial safety regulations. Occasionally, a worker will be exposed to the blow-back of hazardous materials, with the force of the blow-back tending to remove the hard hat. Some eye injuries have been sustained as a result of the goggles being torn away along with the hard hat during a blow-back incident. Such eye injuries are more likely to occur if the strap of the safety goggles is attached directly to the hard hat. That is, the force of the blow-back may be so strong that the helmet will be blasted aside, pulling the goggles along with it, thus exposing the eyes of the wearer to the hazardous blow-back materials.
It will be appreciated that the risk of eye injury is substantially less if the safety goggles are secured about the head and neck of the wearer, that is, worn independently and not attached to the hard hat.